Electric lamp



H. BODEZ ELECTRIC LAMP July 2, 1957 5 Sheets-Sheet l Filed June 5, 1954 July 2, 1957 H. BoDl-:z 2,798,149

ELECTRIC LAMP Filed June s, 1954 5 sheets-sheet 2 Fig. 3

H. BODEZ ELECTRIC LAMP July 2, 1957 l 5 Sheets-Sheet 3 Filed June 3, 1954 ELECTRIC LAMP Henry Boden, Zurich, Switzerland Application June s, 195,4, sensi-N0. 434,229

1 claim.. (Cl-.,z4.11.4)

Electric lamps made known so far and particularly intended for wet rooms may be dividedinto two groups' viz. such with a metallic casi'ng usually serving as a reilector which is made watertight in front by a protective glass, and such. with a metallic casing which is open in front. The first-named type involves the drawback that, within the closed casingv condensed water may form which in tirne leads to destruction of' the lamp by corrosion and rotting, In the second-namedV type of lamps the formation of condensed water is excluded, but the inside of the casing is exposed to dirt, y

The present invention relates to aV lamp particularly adapted for use in wet or damp rooms and 'nV which the aforementioned shortcomings are ob `ated, rljhe lamp accordins t the invention is. essentially characterized. in. that it comprises at-n leastoneI uorescent tube with stabilizer and ignition in, an. air-A and watertight easing; 0f an insulating material; transmitting light at least in pan.

By the use of insulating material for the casing, temr perature variations within^ the casing can be practically avoided so that formation of condensed. water. is exeluded.

Further features of the invention will appear-from'the. speciication, claim and accompanying drawingwhich rep-4 resents by way of example some preferred, fonms of embodiment incorporating the invention-t,

Fig. 1 shows a longitudinal section ot uorescent. lamp;

Fig. 2v is a sectional view taken along `the line lI.-..II. of Fig. l;

Figs. 3 and 4 are longitudinal sections through one end, of a lamp of modified forms;

Fig. 5 is a. longitudinal section through the connection end of a furthermodified form, and

Fig. 6 is a sectional view taken on theliue; of Fig. 5.

The electric lamp as shown in Fig, l incorporates a casing formed ofV an insulatingjpipe, 10.permeableioqlighl and closed at both ends bye/nd plates 11.A and 12 ofinsulatf. ing material. The end plate- 1 1 is, at one extremity of the casing 10 undet-achablyA secured; airand.' watertight, by being for instance welded or cemented' thereto. Accord;-A ing to Fig. l the end plate 12 at the other end of the casing 10 is secured by screws 13 and nuts 14 to a ange ring 15 in turn Welded or cemented to the respective front side of casing 10. Flange ring. 15; and endfplate 12 have a gasket 16 of elasticmaterial', say rubber, interposed therebetween to provide. an. airs and watertight closure of the body.A Instead of, according to Fig. 3, an end plate 12a may be providedwhich for quicker litting is simply screwed through a gasket 16a.l Ainto the casing 10 which is then provided" with` a. femalethread. The whole casing preferably consists of a translucent synthetic material, such as known under the registered trade name Plexiglas. This material has an extremely high insulating property against electricity and heat so as to practically exclude the formation of condensed States Patent Patented July 2,l 1951 ice 2 water within the casing, because the air within it will be substantially kept at constant temperature.

Centrically arranged in the casing 10 is a, fluorescent tube 17 engaging sockets 18 at both ends in` known manner. These are each ixed by screws 19v and nuts 20 to a suitable socket carrier 21 supported on the inner wall of the casing 10. The socket carriers 21 include circular disks Which in size conform to the inner diameter of the casing 10. They preferably consist of the same insulating material as the casing and are each provided with a cylindrical recess 22, wherein the socket 18` tits. Extending parallel to the fluorescent` tube 17 is a tubular rspacer bar 23 which passesv through. the two socket carriers 21. The latter are each detachably mounted on said bar 23 and secured against displacement by a set screw 24. One socket carrier 21 axially abuts on stops 25 of the casing. Located between the socket carrier atthe other end of the lluorescent tube and the removable end plate 1'2 is the stabilizer with Choker 2.65 condenser 27 and ignition device 28 commonly known as a starter necessary for operating the tube. These accessories are mounted on a base plate 2.9. screwed to, cross-members 3 0 which in turn are rigidlyY united to the b ar 23 by welding or soldering. The lluorescent tube with: sockets,` Socket carriers and accessories consequently constitutes anv as-l sembly which, with end plate IZremOVed, may bebOlY inserted inv or withdrawn from the casing 10.

A rubber-sheathed cable 31 for the supply of electric current is introduced watertight, through a,l glandA 32 into the casing of the lamp. Said gland; 32 possesses a nipple 34 screwed through an elastic gasket33. into the removable end plate 12. and has threaded thereon a locknut 35 which contains a,packingpressedagainst thel sheath of the,

cable 31. Two insulated electric conductors 37 are passed through the tubular bar 23 and lead, to the socket 18 remote from the accessories, while twoV further insulated. conductors 38 lead from the stabilizer direct tothe other neighboring socket 1S.

In order that the stabilizer andthe ignition device can-` not be seen through the translucent; insulating pipeV or casing 10, the latter may inside, within the region of these accessories be provided'with an opaque film or layer- (not shown) or else the casing 10 may consist of a material permeable to light, but not transparent.

To exclude the risk of shocks to men due to unskilled manipulation it is also possible toprovideI the removable closure, of the casing as shown. inV Fig. 4. In this shockproof closure the end plate., 12b hasinside two pin sockets 4.0,. screwed therein by which the flanged insulating disk 41 is, at. the same time attached thereto. In this case, in, casing 10, at a, certain distance from. the flange ring 15,

there is a disk 42-v attached tothe spacer bar 23 and which carries twoplug pins 43. Both,Y the sockets 4,0 as well as the pins 43' are fitted with double nuts 44 having electric conductors 45, 46 clamped; therebetween and connecting these respectively to the cable 31 inserted through the gland 32l and to the base plate 29. which carries the accessories. Protectivesleeves 47 of insulating material are arranged to prevent exposure of the sockets 40, and the risk ofshocks tooperatorsA when the end plate; 12b is removed with cable and sockets alive. To close the casing 10Y the end plate 12b has to be screwed up with the ange ring 1 5-v in the same way as described above by interposing a gasketv 16.

According to a further feature of the. invention, the

lamp may also be provided. so that it can not only be;

lamp so that, if any explosive gases should penetrate the open lamp, their ignition is impossible.

Such a form of embodiment is shown in Figs. and 6, where the body of the lamp includes two end plates 50 and 51 of translucent insulating material, whose diameter is greater than that of the pipe 10 (Fig. 6). At their flanges projecting beyond the periphery of the body or pipe, the end plates are inconnected by four tie-rods 52 of steel and secured by triangular double nuts 53. VThe end plate 51 is thus pressed through a gasket 54 of brass asbestos towards the body or pipe 10, while the end plate 50 is chemically welded thereto.

The end plate 51 has screwed therein two pin sockets 55 to which the electric leads 56 are connected. To protect these connecting points from contact with pene'trating moisture or explosive gases, the end plate 51 has a protective cover 56 screwed therein through an interposed gasket 57 of brass asbestos. The cable 31 for the supply of electric current is inserted through this protective cover by means of a gland 32 in the aforedescribed way.

Chemically welded to the inner surface of the end plate 51, in side-by-side arrangement, are two parallel tubular sleeves 58 of insulating material and permeable to light, the bottoms 59 thereof being each traversed by a socket 55. The hanged disks 60 and 61 incorporated in the body 1t) are attached to the spacer tube 23, of which one, 61, is designed as socket carrier for the uorescent tube 1'7 and carries screwed-in sockets 62 for the pins thereof. The other disk 60 has two round bars 63 of insulating material fitted therein and chemically welded thereto and which are inserted in the two tubular sleeves 58, each of said bars carrying a plug pin 64 resiliently contacting and engaging the respective socket 55. The pins 64 axially protrude through the respective round bars `63 and extend into the hollow space 65 constituted by two screwed-up disks 60, 61, thus forming a pressure chamber. Attached respectively to the ends of the pins 64 and to the sockets 62 are electric conductors 66 which are passed through an opening 67 in the spacer tube 23 and connected through the same with the stabilizer and starter (not shown) which in this form of embodiment are located at the opposite end of the body of the lamp.

When taking olf the end piece 51 by removing the nuts 53 from the body, at the same time both round bars 63 will be withdrawn from the tubular sleeves 58 and the pins 64 from the sockets 55. Incidentally a rupturing spark will set up in each of them in case of the lamp being alive. If an explosive gas has penetrated into the body 10, it will be ignited by the spark. The explosion, however, will be confined to and is extinguished in the hollow space 68 acting as a pressure chamber since, after the pins 64 have got clear of the sockets, the round bars 63 are still contained by about half their length in the tubular sleeves 58, whereby between these parts a clearance of about 0.2 mm. is provided so that an exit of the explosive gases into the body of the lamp is impossible.

Should, on the other hand, due to gradual slackening of the electric connections in the hollow space 65, sparking with explosion occur, this will also be extinguished in the pressure chamber 65.

The current-carrying parts of the lamp are therefore, besides being dampand moisture-proof, protected threefold from the risk of explosion, viz. (iirst) by the screwed end piece 56 adapted to prevent dangerous gases from entering the body, and (second and third) by the pressure chambers 65 and 68 surrounding the points of connection.

The body of the lamp is protected from external mechanical actions by four steel bars 52 having spaced A' formation of condensed water, since, because of the insulating property of the casing, interiorly the temperature will be kept substantially constant. All essential elements of the lamp, such as tube 17, sockets 18, stabilizer 26, 27 with starter together with the electric conductors 37 and 38 are therefore protected from injurious action of moisany unwanted loosening of the iuorescent tube 17 therefrom due to vibrations during transport or action of heat is practically excluded.

A further advantage of the lamp according to Figs. 5

and 6 is seen in that it may be utilized in rooms Where there is some risk of explosion, which merit need not be discussed in detail.

Alternatively, some forms of the lamp might be conceivable, in which two or more fluorescent tubes are ari. ranged parallel within the insulating pipe or body 10.

What I claim is:

In an electric lamp, particularly for use in moist and wet rooms, the combination comprising a cylindrical casing of light transmitting material, permanently closed at one end thereof by the same material and threaded at the opposite end thereof, such material being a synthetic such as Plexiglas or the like having a high degree of insulating ability against transfer therethrough of electricity or heat, a fluorescent lamp assembly comprising a pair of sockets for receiving the terminals at the opposite ends of a iiuorescent light tube, longitudinally spaced cylindrically shaped carrier discs for said, sockets, said socket carrierdiscs being slidable along and being supported by the wall of said casing, a tubular spacer bar to which said socket carrier discs and the sockets thereon are secured in longitudinally spaced relation, a tubular iiuorescent Vlamp secured between said sockets, said spacer bar enclosing and serving as a duct to carry conductors extending to the socketfor those end terminals of said light tube located adjacent the permanently closed end of said casing and stabilizer and starter units supported upon said spacer bar and connected in the lamp circuit, and a gasketed end plate of the same material as said casing for closing and sealing the threaded end of the latter after said iiuorescent lamp assembly has been slidably inserted into said casing, said end plate being threaded for screw engagement with the threads provided on that end of said casing and being provided with an axial opening therethrough and packing gland cooperative with said opening for leading conductors through said end plate for connection to said lamp assembly.

References Cited in the tile of this patent UNITED STATES PATENTS 1,407,473 Murray Feb. 21, 1922 2,347,174 Cross et al. Apr. 25, 1944 2,382,538 Biiler Aug. 14, 1945 2,472,180 Tittle June 7, 1949 FOREIGN PATENTS 640,250 France Mar. 24, 1928 990,440 France June 6, 1951 

